I can also confirm the same symptoms at the same timeframe as everyone else. At least two of my users are experiencing the buffering on their rokus.
However, I had another major issue with the plex server upgrade at the end of June where the server was down for almost an entire week. This thread talks about that issue and it was resolved after a kernel update that came out a week later and upgrading my BIOS (I believe it was the Spectre upgrade in the kernel that messed me up).
Regardless, after completely reinstalling my server and getting it back up and running, the same buffering issue is seen today. I run the server on a gigabit connection and my friend with the roku has a decent connection as well so bandwidth isn’t an issue, especially since they never had an issue before the update.
